Pipe bending machine



Oct. 22, J L COODY PIPE BENISING MACHINE 5 Sheets-Sheet 1 Filed April18. 1966 Jaw/7 Z. (a0 03/ INVENTOR.

JLL FIIL ATTORNEY Oct. 22, 1968 coopv 3,406,551

PIPEBENDINQ MACHINE Filed April 18, 1966 I 5 Sheets-Sheet 2 J06 Z.(0003/ INVENTOR.

0a. 22, 1968 J. L. coooY 3,4

PIPE BENDING MACHINE 5 Sheets-Sheet 5 Filed April 18. 1966 A rro/wvz rOct. 22, 1968 J. 1.. COODY 3,406,551

PIPE BENDING MACHINE Filed April 18. 1966 S SheetS-Sheet '4 (EA/7 Z.(vac/y 1 VENTOR.

ATTORNEY Oct. 22, 1968 J. L. COODY PIPE BENDING MACHINE 5 Sheets-Sheet 5Filed April 18. 1966 (/bfin Z. (boa y INVENTOR.

United States Patent 01 fice 3,406,551 Patented Oct. 22, 1968 3,406,551PIPE BENDING MACHINE John L. Coody, 7106 Quince St., Houston, Tex. 77017Filed Apr. 18, 1966, Ser. No. 543,427 Claims. (Cl. 72166) ABSTRACT OFTHE DISCLOSURE A pipe bending machine of the type having a supportingbed, along which a pipe is movable along its longitudinal axis andhaving a bending die positioned for engagement with the pipe and aboutwhich the pipe may be bent, and including a bending roller movablymounted for movement toward and away from said longitudinal axis, toposition the roller for coaction with the pipe and die to bend the pipeas the pipe moves longitudinally in one direction along said axis. Theinvention further includes means for moving the pipe longitudinally insaid one direction, and means positioned for coaction with the pipemoving means and the roller to move the roller in a directiontransversely of said axis in engagement with the pipe, during an initiallongitudinal movement of the pipe, to position the roller for suchcoaction with the die to bend the pipe, and thereafter to hold theroller in its adjusted position during subsequent longitudinal movementof the pipe.

This invention relates to a machine for bending pipe and tubulararticles, and more particularly to a machine which may be adjusted toperform a bending operation on pipe whereby bends of predetermined shapeand extent may be accurately reproduced.

The invention has for an important object the provision of pipe bendingapparatus which is adjustable to produce bends having predeterminedcharacteristics and whereby bends of such character may be accuratelyand easily reproduced.

A further object of the invention is to provide pipe bending apparatusby which the cold spring characteristics of pipe may be determined priorto the bending of the pipe and including means whereby such cold springmay be compensated for in forming the bend.

Another object of the invention is the provision of a pipe bendingmachine which is easily adjusted for use with pipes of widely varyingdiameters, which is of simple design and rugged construction, andwherein the parts are easily replaceable for purposes of maintenance andrepair.

The above and other obvious advantages of the invention 'Will beapparent from the following detailed description of a preferredembodiment of the same, when considered in conjunction with the annexeddrawings, wherein- FIGURE 1 is a side elevational view of the pipebending machine of the invention, showing the same with a pipe insertedtherein preliminary to the performance of a bending operation;

FIGURE 2 is a fragmentary, side elevational view of a portion of thebending machine, as illustrated in FIGURE 1, removed from thesurrounding structure of the machine, and showing details of structureof the mechanism by which the longitudinal movement of the pipe in themachine is regulated and indicated;

FIGURE 3 is a fragmentary, side elevational view, on a somewhat enlargedscale, of a portion of the machine, as illustrated in FIGURE 1, showingthe mechanism by which the pipe is gripped and advanced longitudinallyin the machine, the mechanism being shown in its re tracted conditionpreliminary to an advancing movement of the pipe;

FIGURE 4 is a top plan view, on an enlarged scale of the pipe grippingand advancing mechanism of FIG- URE 3, as viewed along the line 4-4 ofFIGURE 3, looking in the direction indicated by the arrows;

FIGURE 5 is a cross-sectional view, taken along the line 55 of FIGURE 4looking in the direction indicated by the arrows;

FIGURE 6 is a cross-sectional view taken along the line 6-6 of FIGURE 5,looking in the direction indicated by the arrows;

FIGURE 7 is a fragmentary, side elevational view, partly broken away,and partly in cross-section and on a greatly enlarged scale showingdetails of structure of the bend forming and regulating mechanism of themachine, the mechanism being shown with a pipe in position therein andwith the parts in the relative positions which they occupy at the end ofan advancing movement of the pipe during a bending operation;

FIGURE 8 is a fragmentary, end elevational view of the mechanism ofFIGURE 7, looking at the right hand end of the same;

FIGURE 9 is a fragmentary, longitudinal, central, cross-sectional viewon a greatly enlarged scale, illustrating a somewhat modified structureof the removable bending die supporting means of the machine;

FIGURE 10 is a diagram illustrating the method by which the adjustmentof the bending mechanism is determined preliminary to the setting of thesame to carrying out of a bending operation to form a bend ofpredetermined character; and

FIGURE 11 is a transverse cross-sectional view, on a greatly enlargedscale, showing details of structure, of a portion of the mechanism bywhich the advancing movement of the pipe is regulated and adjusted.

Referring now to the drawings in greater detail the bending machine ofthe invention includes a bed or frame generally designated 10 of usualconstruction, which may be formed with parallel, spaced apart sidemembers or rails 12, as best shown in FIGURE 6, suitably securedtogether at longitudinally spaced intervals, as by means of cross ties14, and provided with legs 16, by which the bed is supported at adesired elevation above the floor.

Longitudinally spaced pipe supporting rollers 18 and 19 are rotatablymounted on the bed in position to support a pipe P thereon forlongitudinal movement along the bed, and pipe gripping and movingmechanism, generally designated 20 in FIGURES 1, 3 and 4 is also mountedon the bed by which the pipe is progressively moved along a longitudinalaxis during the bending operation.

The pipe moving mechanism 20 includes pipe gripping jaws 22, best shownin FIGURE 4, carried on pivotally mounted arms 24 for movement into andout of gripping engagement with the pipe P and spaced apart parallelpower cylinders 26 are provided by which the jaws are movedlongitudinally of the bed in gripping engagement with the pipe to movethe pipe along the bed. The jaws 22 are formed with external taperingfaces 28 with which an actuating block 30 having correspondinglytapering faces is slidably engageable to move the jaws laterally intogripping engagement with the pipe. The jaws are operatively connected toa jaw actuator cylinder 32 to move the jaws longitudinally in onedirection, relative to the block 30 to grippingly engage the jaws withthe pipe and in the other direction to release the pipe.

In the operation of the equipment, the pipe P is supported on therollers 18 and 19 for longitudinal movement between the jaws 22 and thejaws are moved into gripping engagement with the pipe by actuation ofthe cylinder 32, whereupon the pipe may be moved longitudinally to theright as viewed in FIGURES l, 3 and 4 by actuation of the powercylinders 26. When the pipe has been thus moved longitudinally along thebed by extending the piston rods 27 of cylinders 26, the power cylindersmay be actuated to retract the piston rods, thus releasing the jaws 22and allowing the same to be moved back to position the jaws forregripping with the pipe to again move the pipe longitudinally.

A bending die 34 is suitably supported on the bed in position forengagement with the pipe and about which the pipe is bent during thelongitudinal movement of the pipe along the bed. The die 34 ispreferably of a removable type and is supported in position forengagement with the pipe in a usual manner by conventional means.

The bending die 34 may be removably carried in a supporting block 36,suitably attached to the bed, the die being connected to the block bymeans of coil springs 38,

and being held in a desired position of adjustment in the block by aslidable wedge 40, actuated by a pressure cylinder 42, whereby the dieis rigidly held in contact with the pipe by advancing the wedge in theblock and released therefrom by retracting the wedge.

A somewhat different form of the die adjusting mechanism is illustratedin FIGURE 9, wherein the die 34 is held in engagement with the pipe bymeans of a cam or eccentric 44, rotatably mounted on the block 36 andwhich may be rotated to one position to securely hold the die againstthe pipe and to another position to release the die from the pipe.

The pipe bending mechanism also includes a bending roller 46 mounted forlateral adjustment relative to the die 34 at a location spacedlongitudinally therefrom, as best shown in FIGURE 7. The roller 46 iscarried on an adjustable support member generally designated 48 which ispivotally mounted on the bed, as shown at 50, and formed with an arm 52upon which the roller is rotatably mounted, and an arm 54 by which themember is rotated about the pivot 50 to position the roller at a desiredlocation. The support member 48 is yieldingly urged in a clockwisedirection of rotation on its pivot 50, as viewed in FIGURE 7, bysuitable means, such as the coil spring 51. The arm 52 has a bearingblock 56 thereon which is provided with longitudinally spaced notches 58by which the longitudinal position of the roller 46 on the arm may bevaried.

The arm 54 carries adjusting screws 60 and 62, operated by hand wheels64 and 66, respectively, for the purpose of adjusting the position ofrotation of the support member 48, in a manner to be hereinafterdescribed, whereby the position of the roller 46 is adjusted to bend thepipe. Each of the screws 60 and 62 is provided with a suitable scale,such as those shown at 68 and 70, respectively, by which the setting ofthe screws may be accurately indicated.

For the purpose of actuating the support member 48 a longitudinallymovable carriage block 72 is provided, which is mounted for movementalong inside trackways 74 on the side members 12 of the bed, as seen inFIGURE 6, and which carries an actuating roller 76 at its forward oradvanced end, in position for engagement with a rocker plate 78,rockably mounted on a support block 80 adjustably carried on the arm 54of the member 48 and adjustable laterally thereof by the screw 66, asbest shown in FIGURE 7.

The carriage block 72 has longitudinal grooves 82 in its opposite sidesin which the trackways 74 are slidably fitted. At the end of the blockopposite that upon which the roller 76 is carried, the block 72 has anend bore 84, within which one end of a rod or shaft 86 is fitted, therod being secured to the block by a cross pin 88, forlongitudinalmovement therewith, as best seen in FIGURE 5. The rod 86 isslidably extended through an actuating sleeve 90 attached to theactuating block for movement therewith longitudinally of the bed. Theblock 30 and sleeve may also carry a roller 92 positioned for engagementwith the pipe P to further support the pipe.

The rod or shaft 86 is formed at its other end with a tapered point 94which fits into a similarly shaped socket 96 in the forward or advancedend of an adjustable stop member 98, movably carried on the bed forlongitudinal adjustment thereon, as by means of a screw 100 having anadjusting Wheel 102 and provided with a pointer 104 by which theposition of adjustment of the stop member may be indicated on a scale106 on the bed, as best seen in FIGURE 1.

By this arrangement it will be apparent that upon movement of the pipegripping mechanism to the right as viewed in FIGURE 5, the sleeve 90will move therewith in engagement with the actuator block 72 to move theactuator block to the right, and upon retracting movement of the pipegripping mechanism to the left, as viewed in FIGURE 5, the sleeve 90will be moved out of engagement with the block 72 leaving the block inits advanced position.

The shaft 86 is also formed with an annular groove 108 into which aremovable stop 110 of inverted U-shape may be positioned for engagementwith the left end of the sleeve 90, as viewed in FIGURE 5, to cause theactuator block 72 to move to the left with the sleeve upon retractingmovement of the pipe gripping mechanism when desired.

The rocker plate 78 is positioned for engagement with the roller 76 torotate the plate toward a horizontal position, as seen in FIGURE 7. Whenthe actuator block 78 moves to the right and when the actuator blockreaches its most advanced position to the right it will be past thepivot point of the rocker plate so that the plate will remain horizontalas long as the block is in its advanced position.

Suitable means, such as the stop piece 112 is positioned on the bed forengagement with the plate 78 to limit tilting movement of the platetoward its horizontal position.

A longitudinal, suitably graduated scale 114 is positioned on the bedbelow the roller 46, along which a vertically adjustable pointer 116 ismovable, which pointer may be adjustably clamped to the scale at anyposition of longitudinal adjustment thereon, the pointer being alsoadjustable vertically and being provided with a graduated scale 118 bywhich the vertical position of the pointer is indicated.

In the operation of the machine, the pipe to be bent is supported on thebed by the rollers 18 and 92, the die 34 being released and the pipeextended through the die support 36. The pipe gripping mechanism will bein its retracted and released position, the stop member 110 being inposition in the groove 108 of shaft 86 and the sleeve 90 and actuatorblock 72 being in their retracted positions to the left as viewed inFIGURES 1 and 5.

The radius of the bend to be formed having been given, the positioningof the bending roller 46 may be determined diagrammatically by a diagramsuch as that shown in FIGURE 10, wherein the radius of the bend to beformed is represented by the distance from the point C to the point A.Using the point C as center, an arc is then drawn from point A to apoint D which are represents the number of degrees of the bend to beformed by one stroke of the pipe gripping mechanism. The radius frompoint C to point A is then continued radially outwardly for a distanceequal to the external diameter of the pipe P to a point B, whichrepresents diagrammatically the point at which the roller 46 engagespipe P at the beginning of a bending stroke of the machine. The radiusfrom point C to point D is similarly extended to point F, which thenrepresents the point at which the bending roller 46 will engage the pipeP at the end of the bending stroke. The distance from the point F to theradius through the point A will then be the longitudinal distancethrough which pipe P will move during one stroke, while the distance ofthe point F from a line at right angles to the radius through point Bwill be the vertical distance through which the roller 46 will moveduring one stroke.

The arcuate distance from point A to point D is the length of the arc ofthe bend formed during one stroke of the machine.

The position of the center 47 of the roller 46 at the beginning of abending stroke is represented by the point H which will be on a linepassing through point B and parallel to the axis of the pipe P, and theposition of the center 47 of the roller 46 at the end of the stroke isrepresented by point F, down from the center of the pivot pin 50 throughpoint H.

At the beginning of the initial bending stroke of the machine the roller46 will be in the position shown in FIGURE 1 and at the end of thestroke the roller will occupy the position of FIGURE 7 which is somewhatabove and to the left of the position of FIGURE 1. By suitablypositioning the pointer 116 on the scale 114 and adjusting the verticalposition of the pointer by the scale 118, the pointer may be set toindicate the position to which the center of the roller will move whenthe pipe reaches the end of a bending stroke. In setting the point ofthe pointer 116 at the proper location the pointer is moved to aposition on scale 114 representing the distance between points E and Fon the diagram of FIGURE 10, after which the pointer is moved verticallyuntil the distance between points H and F on the diagram is representedon scale 118.

Having determined by the above described means the position to which thebending roller 46 will be moved upon completion of the first pipeadvancing stroke of the machine, the pipe gripping mechanism is actuatedto move the block 30 and sleeve 90 to the right, as viewed in FIG- UREl, to advance the carriage block 72 and the roller 76 therewith to theposition of FIGURE 7 in engagement with plate 78, whereupon hand wheel66 is rotated to cause the arm 52 of support member 48 to swing upwardlyto move the roller 46 to the desired position as indicated on the scale68. During such adjustment of the roller 46 the pipe P will be lifted bythe roller, the die 34 being free to move upwardly with the pipe.

With the roller 46 thus adjusted to its uppermost position, the pipegripping mechanism is retracted to move the roller 76 therewith to theleft, as viewed in FIGURE 7, thus allowing the plate 78 to tilt counterclockwise and the roller support 48 to rotate clockwise under theinfluence of the spring 51 to retract the roller 46. As the roller 46 isretracted the pipe P moves downwardly to its horizontal position on thebed and the die 34 is then tightened into engagement with the pipe byoperation of the wedge 40. With the pipe thus positioned the hand wheel64 is rotated to engage the screw 60 with plate 78.

The adjustments having been made, as described above, the pipe grippingmechanism is then actuated to advance the pipe P to the right throughthe initial stroke of the machine, the plate 78 and the roller 76 inengagement therewith coacting to move the bending roller 46 upwardlyduring longitudinal movement of the pipe to the right, as seen in FIGURE7, to bend the pipe about the die 34.

At the end of the first bending stroke of the machine the stop member110 is removed from the groove 108 of shaft 86, so that the carriageblock 72 and roller 76 will remain in advanced position when thegripping mechanism is retracted, thus holding the bending roller 46 inits upmost position during subsequent pipe advancing strokes of themachine. By then repeating pipe advancing strokes of the machine a bendof any desired extent, of a predetermined radius may then be produced inthe pipe.

For the purpose of determining the angular extent to which the pipe isbent, a suitable gauge having a circular dial 120, graduated in degrees,and provided with a pivotally supported gravity actuated pointer 122 issuitably supported on the pipe P outwardly beyond the roller 46, as bymeans of a releasable clamp 124 in position to indicate the angularextent of the bend produced.

Under some circumstances, such as in the bending of pipe which is madeof resilient or springy material, such as steel pipe, it may bedesirable to accurately determine the tendency of such pipe tostraighten when released after the production of a bend, such tendencybeing com gnonly referred to as cold spring. To measure the cold springof the pipe, a bend is formed in the pipe by the method described above,the extent of the bend being noted on the dial 120, whereupon thebending roller 46 is retracted somewhat to allow the bend to relax, thecold spring being then indicated by the resulting change in the positionof the pointer 122 on the dial.

Having thus determined the amount of the cold spring for the particularpipe under treatment, it is only necessary to adjust the machine toproduce a bend which exceeds the desired bend by the amount of the coldspring as shown on the dial and the pipe will assume the desired bendwhen released.

To enable the machine to be readily employed for the production of coilsor helices of pipe, suitable means, such as the washer 126, shown inFIGURE 8, may be positioned on the shaft which supports the roller 46between the roller and the adjacent inside face of the bearing block 56to position the roller in laterally offset relation to the axis of thepipe P, whereby the pipe will be formed into helical turns by acontinuance of the bending operation.

Suitable means, such as control valve mechanism, not shown, may, ofcourse, be provided in the hydraulic sup ply lines of the powercylinders 26 and the jaw actuating cylinder 32, whereby the operation ofthese cylinders may be coordinated to grip and advance the pipe Plongitudinally during a bending stroke of the machine and to release thesame upon retracting movement of the pipe gripping mechanism.

It will thus be seen that the invention constructed and operated asdescribed above provides a pipe bending machine which may be employedfor the bending of pipe of various sizes and materials and wherein meansis provided for adjusting the machine to accurately reproduce bendsthroughout a wide range of shapes and sizes.

The invention is disclosed herein in connection with a particularconstruction and arrangement of the parts, which it will be understoodis intended by way of illustration only, it being evident that variousmodifications can be made therein within the spirit of the invention andthe scope of the appended claims.

Having thus clearly shown and described the invention, what is claimedas new and desired to secure by Letters Patent, is:

1. In a machine for bending pipe a supporting frame, means forsupporting a pipe for movement along a longitudinal axis, a bending diepositioned to be engaged by the pipe and about which the pipe may bebent, a bending roller movably supported on the frame for movementtoward and away from said axis to move the roller into and out of aposition for coaction with said die in engagement with the pipe to bendthe pipe upon longitudinal movement of the pipe along said axis, pipegripping means movably mounted on the frame for movement therealong inparallel relation to said axis and for movement into and out of grippingengagement with the pipe and means for moving said gripping means intogripping engagement with the pipe to impart longitudinal movement to thepipe in one direction along said axis with said gripping means, and outof such gripping engagement to allow longitudinal movement of saidgripping means in the other direction independently of the pipe.

2. The pipe bending machine of claim 1 including means for moving saidbending roller into said position for coaction with said die and meanspositioned for coaction with said roller moving means and said pipegripping means to move the roller into said position upon movement ofsaid pipe gripping means in said one direction.

7 3. The pipe bending machine of claim 1 including References Citedmeans for holding said bending roller in said position for UNITED STATESPATENTS coaction with said die during movement of said pipe l grippingmechanism in said other direction. 22 5" 4. The pipe bending machine ofclaim 1 including 5 1568573 1/1926 Smith means for limiting thelongitudinal movement of said pipe 2245407 6/1941 Lignia-I; 72 166gripping means to cause said roller to be moved to a pre- 3:145:7568/1964 Hm 72 421 determined position relative tosaid die uponlongitudinal movement of said gripping means in said one direction.FOREIGN PATENTS 5. The pipe bending machine of claim 1 including 101,194,809 6/ 1965 Germany. means for moving said roller toward said axisin response to longitudinal movement of said gripping means in oneCHARLES LANHAM, Primary Examine"- direction in gripping engagement withsaid pipe. E. M. COMES, AssistantExamin er.

